CSA has been associated with a variety of adverse sequelae, including engaging in risky sexual behaviors. Individuals who were sexually abused as children report an earlier age of first consensual intercourse (e.g., Wilsnack, Vogeltanz, Klassen, & Harris, 1997), more unprotected sex (e.g., Lodico & DiClemente, 1994), and a greater number of sexual partners (e.g., Greenberg et al., 1999; Holmes, Foa, & Sammel, 2005). Individuals who were sexually abused as children also are more likely to have engaged in commercial sex work (e.g., Kalichman, Gore-Felton, Benotsch, Cage, & Rompa, 2004). A recent meta-analysis concluded that, among women, CSA was associated with unprotected sex, multiple partners, sex trading, and adult sexual revictimization (Arriola, Louden, Doldren, & Fortenberry, 2005). Individuals who were sexually abused as children are more likely to have an incident STD (e.g., Wingood & DiClemente, 1997), to have a greater number of lifetime STDs (e.g., Greenberg et al., 1999), and to be infected with HIV (e.g., Kalichman et al., 2004).

Miller (1999) proposed a conceptual model to explain the link between CSA and later risky sex. Miller hypothesized that CSA leads to sexual risk behaviors through four mechanisms: (a) using substances to cope with the abuse; (b) mental illness due to the abuse; (c) riskier social networks; and (d) poorer sexual adjustment. Focusing on men who were sexually abused as boys, Purcell, Malow, Dolezal, and Carballo-Diequez (2004) hypothesized that CSA may influence later sexual risk behaviors through mediating variables such as substance use, psychological distress, sexual dysfunction, and revictimization.

Portions of the conceptualizations provided by Miller (1999) and Purcell et al. (2004) have received indirect empirical support. That is, empirical research has linked CSA with each of these proposed mediators, including alcohol (e.g., Bartholow et al., 1994; DiIorio, Hartwell, & Hansen, 2002) and drug use (e.g., Kalichman et al., 2004; Nagy, DiClemente, & Adcock, 1995), substance use before sex (e.g., Lodico & DiClemente, 1994), partner violence (e.g., Cohen et al., 2000; Wingood & DiClemente, 1997), and mental health problems (e.g., Epstein, Saunders, Kilpatrick, & Resnick, 1998; Nagy et al., 1995). Further, each of these proposed mediators have been associated with risky sexual behavior; thus, there is evidence of the substance use—risky sex link [e.g., Fortenberry (1995), George & Stoner (2000), Leigh & Stall (1993)], the link between partner violence and risky sex [e.g., Bauer et al. (2002), Garcia-Moreno, Jansen, Ellsberg, Heise, & Watts (2005), Gilbert, El-Bassel, Schiling, Wada, & Bennet (2000), Testa, VanZile-Tamsen, & Livingston (2005)], and for the depression—risky sex link [e.g., Hallfors, Waller, Bauer, Ford, & Halpern (2005), Hutton, Lyketos, Zenilman, Thompson, & Erbelding (2004)].

Building on these conceptual and empirical foundations, we propose a conceptual framework in which CSA leads to increased alcohol and drug use, partner violence, and depression; these variables, in turn, increase the likelihood of sexual risk behavior. Thus, even though the association between CSA and substance use, mental health, and partner violence is well-documented, most studies have focused on the latter as outcomes of CSA, rather than as potential mediators of the relation between CSA and risky sexual behavior. The current study advances prior research by examining the mediation of the CSA—risky sexual behavior link. In addition, we hypothesize that the role that these potential mediating variables play will differ for males and females. The majority of studies of CSA have sampled only men or women, precluding gender comparisons. However, findings from several studies indicate that the relation between CSA and potential mediators (i.e., substance use, mental health, and partner violence) differs for men and women. For example, studies have found that CSA is associated with: (a) greater alcohol use for women, but not for men (Brown et al., 1997); (b) drinking before sex for men, but not women (Lodico & DiClemente, 1994); and (c) depression for girls, but not for boys (Nagy, Adcock, & Nagy, 1994). These different patterns of association suggest that gender may be an important moderator of the CSA—risky sexual behavior relationship.

Finally, few studies have investigated CSA among patients attending an STD clinic. This omission is important because adults seeking care for a STD are at disproportionately higher risk of contracting HIV (Weinstock, Dale, Linley, & Gwinn, 2002); in addition, among male STD clinic patients, CSA rates are higher than what is found for the general population (Bartholow et al., 1994; DiIorio et al., 2002; Doll et al., 1992), making it especially important to study CSA in this population.

There are several possible reasons why the rate of CSA was so high in our sample, relative to the general population. First, it is likely that patients recruited from a public STD clinic, which serves many patients without health insurance or a private physician, have experienced a variety of adverse life events, including CSA. This explanation corroborates results from other studies of men attending an STD clinic in which similarly high rates (25–37%) have been observed (Bartholow et al., 1994; DiIorio et al., 2002; Doll et al., 1992). The rates obtained for women are more difficult to interpret because of the relatively few studies investigating females attending public STD clinics (Thompson, Potter, Sanderson, & Maibach, 1997).

A second explanation for the high CSA rates observed in this study involves the methods of the current study; that is, we used an ACASI survey (completed in a private exam room), which may have led participants to feel more comfortable revealing sensitive information about childhood sexual experiences, which may have led to greater rates of reported CSA. Indeed, prior research suggests that ACASI often results in more reporting of sensitive behaviors (e.g., Des Jarlais et al., 1999; Metzger et al., 2000).

Third, the definition of CSA, which included both age discrepancy and use of force, also may have led to the relatively high rate of CSA reported in this study. If only childhood sexual experiences involving force had been included, the rates of CSA would have been lower (34% of women and 15% of men) and more similar to national prevalence estimates (30% of women and 15% of men). However, studies using both age discrepancy and force in the definition of CSA have found much lower rates of CSA than the present study (e.g., Briere & Elliott, 2003; Vogeltanz et al., 1999). In addition, the definition of CSA we used was relatively strict, in that only sexual experiences involving oral, vaginal, or anal sex were classified as CSA; other studies have included any sexual activity, including kissing or touching, in the definition of CSA (e.g., Briere & Elliott, 2003; Vogeltanz et al., 1999). Research needs to explore which explanation(s) can best account for the high rates of CSA observed in our sample.

A second noteworthy finding was that a similar percentage of men and women reported CSA. This finding contrasts to studies of the general population that have found higher rates of CSA among women than men (Briere & Elliott, 2003; Finkelhor et al., 1990). We did find that women were more likely than were men to report a childhood sexual experience involving force. This finding suggests that men may not perceive childhood sexual experiences with older individuals as necessarily coercive, and extends previous research suggesting that men often do not perceive these childhood sexual experiences as negatively as women do (Rind et al., 1998). Researchers could conduct follow-up qualitative interviews with participants who report a childhood sexual experience with a significantly older partner that does not involve force, to clarify participants’ perceptions of these experiences.

A third set of findings was that CSA was associated with sexual behavior in adulthood that puts participants at risk for contracting an STD. Participants who were sexually abused reported a greater number of lifetime sexual partners, a greater number of partners in the past three months, a greater number of episodes of unprotected sex in the past three months, and were more likely to have exchanged sex for money or drugs and to have been diagnosed with an STD. Overall, there was a consistent pattern of riskier sexual behavior among participants with a history of CSA. These findings corroborate results from other studies (e.g., Kalichman et al., 2004; Wingood & DiClemente, 1997), including several that have investigated patients attending STD clinics. In STD clinic samples, CSA has been associated with a variety of risk behaviors and outcomes, including exchanging sex for money or drugs (Bartholow et al., 1994; DiIorio et al., 2002), having a greater number of partners (DiIorio et al., 2002), and having multiple partners (Thompson et al., 1997). The magnitude of the CSA-risky sex association tends to be modest, consistent with the notion that sexual behavior has many determinants, not just CSA.

The exception to the riskier pattern among CSA patients involved condom use with an outside partner; on this risk marker, CSA patients did not differ from non-CSA patients. One hypothesis for this (non) finding is that all patients, even those with a history of CSA, are more likely to protect themselves in what they perceive to be the riskiest relationships (i.e., sex with casual or non-regular partners). The equivalent rates of condom use for CSA and non-CSA patients in non-regular relationships contrast with condom rates in steady relationships, where patients with a history of CSA were more likely than non-CSA patients to engage in unprotected sex. Thus, CSA survivors may be more vulnerable in primary partnerships where they (especially women) fear partner reprisal (O'Leary, 2000). This hypothesis warrants further study.

The fourth major finding concerns the possible mediators of the CSA-risky sex relationship. Overall, our research partially supported Miller’s (1999) and Purcell et al.’s (2004) conceptualization of the association between CSA and risky sex, with substance use and partner violence (for women) mediating the relation between CSA and risky sex. For the sample as a whole, the co-occurrence of alcohol use and sex, drug use, and the co-occurrence of drug use and sex partially mediated the relation between CSA and the number of partners in the last 3 months; thus, CSA was associated with greater substance use and misuse, which, in turn, was associated with having more partners. These findings suggest that CSA increases a person’s vulnerability to alcohol and drug abuse, perhaps as a way of coping with the CSA experience or other life stressors (Schumm, Hobfoll, & Keogh, 2004; Wilsnack et al., 1997). This alcohol and drug use may, in turn, lead to a greater number of sexual partners. Consistent with alcohol myopia theory (Steele & Josephs, 1990), alcohol use may lead to risky sexual behavior by reducing information processing capacity, which causes a person under the influence of alcohol to attend to the most immediate cues (e.g., attractive person, sexual arousal, intimacy needs), while reducing a person’s capacity to attend to more distal cues (e.g., concerns over pregnancy, HIV or other STDs). Substance use may also be associated with a greater number of sexual partners through sex work, as women and men with few financial resources may exchange sex for money or drugs.

In contrast, substance use did not mediate the association between CSA and the number of unprotected sex acts in the past 3 months. Indeed, for the sample as a whole, none of the variables mediated the association between CSA and unprotected sex. Although all of the mediators were related to CSA, they were not related to the number of episodes of unprotected sex. Clearly, the relationship between substance use and sexual behavior is complex, and requires additional fine-grained (i.e., event-level; Vanable et al., 2004; Weinhardt & Carey, 2000) analyses that were not possible with the methods used in this study.

Interestingly, although depression was associated with CSA, depression was unrelated to the number of sexual partners or the number of episodes of unprotected sex; thus, depression did not mediate the relation between CSA and risky sexual behavior. This finding is consistent with recent evidence suggesting that there may be no relation between depression and sexual behavior (Crepaz & Marks, 2001), especially when controlling for other possible determinants of risk behavior. Although we did not find support for the CSA—mental health—risky sex association proposed by Miller (1999) and Purcell et al. (2004), it is important to note that depression is only one aspect of mental health; other mental health markers (or more precise indicators of depression) should be investigated further.

The fifth major finding from this study was that gender moderated the mediated relations between CSA and risky sex. The co-occurrence of drug use and sex mediated the relation between CSA and the number of partners for women, but not for men (i.e., the co-occurrence of drug use and sex related to the number of partners in the past three months only for women). The association between drug use and sex, and the number of partners for women, may be partially explained by the greater percentage of women in the sample who reported exchanging sex for money or drugs.

Additionally, partner violence mediated the association between CSA and the number of episodes of unprotected sex for women only. Although CSA was associated with partner violence for both men and women, partner violence, in turn, was associated with a greater number of unprotected sex acts in the past three months only for women. It is likely that women currently in violent relationships may fear physical harm if they ask their partner to use a condom; individuals who were in violent relationships in the past may have learned that asking their partner to use a condom resulted in physical reprisal and, therefore the behavior of asking a partner to use a condom is suppressed (O'Leary, 2000). Men, who are usually physically stronger, likely are less fearful of physical harm from a partner if they ask to use a condom.

Although the moderated mediation analyses did not find gender differences related to alcohol use, the co-occurrence of alcohol use and sex mediated the relation between CSA and the number of partners for men but not for women. Some studies report gender differences in alcohol expectancy effects, with men who believed that they were drinking alcohol becoming more sexually aroused than men who did not think they were drinking alcohol; these expectancy effects were not found for women (see George & Stoner, 2000, for a review), potentially explaining the association between the co-occurrence of alcohol use and sex and the number of partners.

The findings from this study have several implications. First, health care providers should be aware of the high percentage of STD patients who report being sexually abused as children, and the impact this experience may have on patients’ current sexual behavior. Clinicians should question patients about CSA, including whether they were forced or coerced, and be prepared to provide referrals for specialized counseling. Several promising interventions have been developed to promote sexual adjustment and reduce sexual risk among CSA survivors (e.g., Chin, Wyatt, Carmona, Loeb, & Myers, 2004; Spiegel, Classen, Thurston, & Butler, 2004), although these interventions need evaluation and refinement to optimize their efficacy (O'Leary, Koenig, & Doll, 2004).

Second, it may be important to design sexual risk reduction interventions specifically for individuals who have been sexually abused as children. Only limited evidence is available to suggest whether an intervention that emphasizes (a) current sexual risk reduction, or (b) the trauma of the CSA experience, or (c) both the CSA trauma and current sexual risk reduction is the most effective in preventing STDs and HIV. Greenberg (2001) found that an intervention addressing only sexual risk reduction was more effective among individuals with a history of CSA than among non-abused individuals. In an intervention for women infected with HIV, those who participated in a group addressing both CSA trauma and impact as well as sexual risk reduction reported greater reductions in sexual risk behaviors than women in an attention control group (Wyatt et al., 2004). Based on pilot data, Spiegel et al. (2004) concluded that a trauma-focused group for women with CSA may be more effective in reducing HIV-risk behavior than a group focused on present difficulties. Continued exploration of the relative effectiveness, and optimal sequencing, of trauma-focused, sexual risk-reduction-focused, and dual-focused interventions is necessary.

Third, the findings from this study suggest potential intervention content. A trauma-focused intervention might attempt to help participants understand how CSA can lead to substance use to cope with the trauma, and could teach participants coping and harm reduction strategies. Discussion might focus on how CSA can predispose survivors to be more vulnerable to abusive partners, and could include instruction in female-controlled risk reduction methods (O'Leary, 2000), as well as referrals for domestic violence shelters. A safer-sex focused intervention might focus on substance use as a trigger for risky sex, and help participants to develop self-management and problem-solving skills to avoid or manage this trigger. Indeed, initial evidence suggests that alcohol and drug treatment can reduce risky sexual behavior (Avins et al., 1997; Eldridge et al., 1997). The intervention could also include a problem-solving discussion about creative ways to be safer if your partner becomes violent when asked to use a condom.

Fourth, these findings suggest that risk reduction interventions for individuals who were sexually abused should be developed separately for men and women. Due to the sensitive nature of both CSA and sexual behavior, most participants will feel more comfortable in a group with members of the same sex. Furthermore, intervention content should differ for men and women, because different variables mediated the relation between CSA and risky sex for men and women. Women’s interventions should emphasize drug use and partner violence, whereas men’s interventions should emphasize alcohol use.

The primary limitation of this study is the use of a cross-sectional approach. It is important to note that causality cannot be determined from correlational data. We acknowledge that the variables specified in the model may be correlated through variables that were not included in the model; for example, poor family functioning may lead to CSA, to substance use, and to a greater number of sexual partners. Although the theoretical frameworks proposed by Miller (1999) and Purcell et al. (2004) support the conceptualization of substance use, partner violence, and depression as potential mediators of the relation between CSA and risky sexual behavior, longitudinal research is needed to understand the direction of these associations.

A second limitation involves the measurement of the mediator variables. Although the violence measure we used did not provide detailed information about the nature of the partner violence, previous studies indicate that lifetime history and recent partner violence both correlate with sexual risk behavior and outcomes (e.g., Bauer et al., 2002). In addition, the substance use variables measured global substance use as well as the association between substance use and sex but did not include extensive event-level data. Event-level assessments provide rich data but are difficult to obtain in large field trials (George & Stoner, 2000; Weinhardt & Carey, 2000).

Future investigators may want to employ a structural equation modeling approach to investigating mediators of the relation between CSA and sexual behavior, in which multiple measures of each construct are used. This approach allows researchers to better assess the constructs of interest, and measurement error can be incorporated into the model. However, it may be difficult to create a latent sexual risk behavior construct, because sexual risk behaviors may be unrelated to each other, as was the case with the number of sexual partners and the number of episodes of unprotected sex in the present study. Research should also investigate how changing the definition of CSA (e.g., non-contact CSA vs. CSA where force was used) affects risky sex outcomes and mediators, and explore mediational relations using condom use by partner type as an outcome.